Band structure modification of the thermoelectric Heusler-phase TiFe2Sn via Mn substitutionElectronic supplementary information (ESI) available. See DOI: 10.1039/c7cp02744c

• Main Authors: Zou, Tianhua, Jia, Tiantian, Xie, Wenjie, Zhang, Yongsheng, Widenmeyer, Marc, Xiao, Xingxing, Weidenkaff, Anke
• Format: Journal Article
• Language: English
• Published: 19.07.2017
• ISSN: 1463-9076; 1463-9084
• DOI: 10.1039/c7cp02744c

Doping (or substitution)-induced modification of the electronic structure to increase the electronic density of states (eDOS) near the Fermi level is considered as an effective strategy to enhance the Seebeck coefficient, and may consequently boost the thermoelectric performance. Through density-functional theory calculations of Mn-substituted TiFe 2− x Mn x Sn compounds, we demonstrate that the d-states of the substituted Mn atoms induce a strong resonant level near the Fermi energy. Our experimental results are in good agreement with the calculations. They show that Mn substitution results in a large increase of the Seebeck coefficient, arising from an enhanced eDOS in Heusler compounds. The results prove that a proper substitution position and element selection can increase the eDOS, leading to a higher Seebeck coefficient and thermoelectric performance of ecofriendly materials. Doping (or substitution)-induced modification of the electronic structure to increase the electronic density of states (eDOS) near the Fermi level is considered as an effective strategy to enhance the Seebeck coefficient, and may consequently boost the thermoelectric performance.